One type of prior art high voltage power supply includes an AC power source having a frequency between 20 and 100 KHz. The source drives a high voltage rectifier including a low voltage primary and a high voltage secondary winding that drives a diode bridge network. The maximum frequency has been confined to approximately 100 KHz because diodes employed in the rectifier are power devices, incapable of recovering adequately if driven at frequencies in excess of 100 KHz. However, because frequencies less than 100 KHz are employed, magnetic core components employed in the transformer are large and heavy. In addition, the magnetic core components are relatively expensive, as are the power diodes employed in the rectifier. These factors concerning size, weight and cost detract from the viability of the prior art high voltage supplies for use in missles and/or airborne systems to energize high voltage electrodes, such as the helix and collector electrodes of a traveling wave tube.
The described prior art high voltage power supplies also are subject to arcing and associated discharge problems, unless appropriate precautions are taken. This occurs even though the high voltage transformers are relatively large. The breakdown problems are likely to occur because ground and high voltage are inside the transformer. To obviate this problem, it has been necessary in the prior art to employ critical and exotic potting techniques and structures.
A further problem with the prior art single power transformer approach is heating due to losses in the power diodes and transformer core. The diodes generally are located in a small volume, where the power and heat dissipated thereby is concentrated. Hence, the heat dissipation problem could be obviated by distributing the diodes over a large surface area.
It is, accordingly, an object of the present invention to provide a new and improved high voltage power supply particularly adapted to supply vacuum tube electrodes.
Another object of the present invention is to provide a new and improved relatively low cost and low volume high voltage power supply for the collector and helix of a traveling wave tube.
Another object of the present invention is to provide a new and improved high voltage DC power supply that achieves low cost and small volume requirements of missles and/or airborne systems through the use of magnetic circuit elements that are operated at frequencies in excess of 100 KHz.
An additional object of the invention is to provide a new and improved high voltage DC power supply employing rectifiers having inexpensive signal switching diodes, instead of expensive power switching diodes.
Still a further object of the invention is to provide a new and improved high voltage DC switched power supply employing switching diodes distributed over a relatively large surface area to avoid heat dissipation problems associated with power diodes located in a relatively small volume.
A further object of the invention is to provide a new and improved high voltage DC power supply employing many transformers distributed over a relatively large surface area to avoid breakdown problems attendant with high voltage power supplies employing a single transformer.